(Reuters) - The uncertainty over automatic cuts in U.S. defense spending to be triggered in January because of congressional inaction has spread to the engineers and project managers in South Florida's aerospace industry.

Employees at Pratt & Whitney Rocketdyne here say that both personal and corporate planning is on hold, with any new ideas of spending being reined in.

Fernando Diaz, 37, deputy program manager for Pratt's RL-10 rocket engine, said he and his wife of two years wanted to start a family. But now they aren't sure if the time is right.

James Larkin, 51, a jet engineer at Pratt, has been through several boom-and-bust cycles, but describes automatic cuts as "a ticking time bomb" for him.

With two teenagers at home, Larkin is worrying about how he will pay for college tuition if the cuts come. He's recruiting fellow employees to raise awareness and write to Congress.